--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pgtoolkit/delayedquery.py	Fri Nov 25 18:17:27 2011 +0100
@@ -0,0 +1,46 @@
+import threading
+import time
+
+
+class DelayedQueryThread(threading.Thread):
+    def __init__(self, targetdbm, targetname, delay, query, args):
+        threading.Thread.__init__(self)
+        self.targetdbm = targetdbm
+        self.targetname = targetname
+        self.delay = delay
+        self.query = query
+        self.args = args
+        
+    def run(self):
+        time.sleep(self.delay)
+        with self.targetdbm.cursor(self.targetname) as curs:
+            curs.execute(self.query, self.args)
+
+
+class DelayedQuery:
+    def __init__(self, targetdbm):
+        '''Initialize DelayedQuery.
+        
+        targetdbm -- PgManager-like object
+        
+        '''
+        self.targetdbm = targetdbm
+        self.queryids = set()
+
+    def add(self, delay, query, args, targetname='default', queryid=None):
+        '''Add query to schedule.
+        
+        delay -- how long to wait, in seconds
+        query, args -- query to be run after delay
+        targetname -- name of connection in PgManager
+        queryid -- discard if query with same id is already scheduled
+        
+        '''
+        if queryid is not None:
+            if queryid in self.queryids:
+                return
+            self.queryids.add(queryid)
+        
+        t = DelayedQueryThread(self.targetdbm, targetname, delay, query, args)
+        t.start()
+